In ViewMate and ViewMate Deluxe (which don't have this tool) you need to do a visual inspection. This can be done by setting the layer colors for the two layers to examine to contrasting colors (red and green work well for this - if set this way where the two layers match the displayed color will be yellow, so whenever you see red or green you know that those parts exist in only one of the layers).You need to make visible only the two layers that you are investigating (if there are more than two layers loaded). You can do this by using the